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Myocarditis

Myocarditis

Overview

Myocarditis is inflammation and weakness of the heart muscle usually caused by a viral infection that reaches the heart, such as the influenza (flu) virus, Coxsackie virus, and adenovirus. Myocarditis can damage the heart muscle causing it to become thick and swollen. This leads to symptoms of heart failure. Myocarditis may also occur during or after other viral or bacterial infections such as polio, rubella, Lyme disease, and others.

Review Date 2/27/2024

Updated by: Thomas S. Metkus, MD, Assistant Professor of Medicine and Surgery, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.